Tentacle

The tentacle is an ambient enemy featured in Doom Eternal.

It appears in various levels, popping out of fleshy holes in the ground when the player comes near. It lashes out for minor damage, then dives back into its hole. After it pops out, it is vulnerable for a brief moment before it attacks, allowing the player to kill it in that time, especially with a burst weapon like the shotgun. Tentacles can be killed with the chainsaw or Crucible, unlike other Ambient demons. Like the Cueball they can't be stunned.

Codex Entry
"The subject of great scrutiny for ARC scientists on Earth, these Hellgrowth formations have appeared all over the planet, taking hold wherever Hell has made its presence known. Forming chaotic, seemingly random structural patterns, the propagation of hellgrowth has taken root at an alarming rate, exhibiting a cellular reproduction cycle that ARC scientists fear may become impossible to contain. The resultant environmental effect is extremely hostile to terrestrial life, producing atmospheric bio-contagens and a multitude of organic hazards. Wherever these nest-like formations emerge, they are protected by swaths of defensive tendrils - long-thorned tentacles that demonstrate keen awareness of their surroundings, fully capable of disembowling(sic) anything that it deems to be a potential threat to the nest."

- Codex